API Reference

SyntheticData

class amisrsynthdata.syntheticdata.SyntheticData(config)[source]

Bases: object

Class for creating synthetic amisr data based on config options.

Parameters:

config (yaml) – Configuration parameters

create_hdf5_output(outfilename)[source]

Generate output parameter arrays and save them to an hdf5 file.

Parameters:

outfilename (str) – Name of output file

create_summary_plots(plot_time=None, plot_beam=None, output_prefix='synthdata_summary_', alt_slices=[100000.0, 200000.0, 300000.0, 400000.0, 500000.0], slice_xrng=[-500000.0, 500000.0, 10000.0], slice_yrng=[-200000.0, 800000.0, 10000.0], dens_colors={'cmap': 'viridis', 'vmax': 400000000000.0, 'vmin': 0.0}, itemp_colors={'cmap': 'magma', 'vmax': 3000.0, 'vmin': 0.0}, etemp_colors={'cmap': 'inferno', 'vmax': 5000.0, 'vmin': 0.0}, vlos_colors={'cmap': 'coolwarm', 'vmax': 500.0, 'vmin': -500.0})[source]

Create basic summary plots of the synthetic dataset. These are thumbnail plots intended to confirm you set up your dataset correctly rather than for any kind of analysis. They include altitude slices of the ionosphere at different altitudes, a RTI plot of a particular beam, and a 3D plot of the full radar FoV. A seperate png will be created for each of the four ISR parameters.

Parameters:

  • plot_time (datetime.datetime) – Time to plot in the aliude slice and 3D FoV plots

  • plot_beam (float) – Beamcode of beam to plot for the RTI

  • output_prefix (str) – Start of the name of the saved output plots, including path

  • alt_slices (list of floats) – Altitudes at which to create the slice plots

  • slice_xrng (list of floats) – Definition of the horizontal grid in the x-drection (start, stop, step)

  • slice_yrng (list of floats) – Definition of the horizontal grid in the y-drection (start, stop, step)

  • dens_colors (dict) – Dictionary listing plotting parameters for electron density, specifically vmin, vmax, and cmap

  • itemp_colors (dict) – Dictionary listing plotting parameters for ion temperature, specifically vmin, vmax, and cmap

  • etemp_colors (dict) – Dictionary listing plotting parameters for electron temperature, specifically vmin, vmax, and cmap

  • vlos_colors (dict) – Dictionary listing plotting parameters for line-of-sight velocity, specifically vmin, vmax, and cmap

generate_beamcodes()[source]

Generate beamcode array. This is a Nbeam x 4 array where the four columns are beamcode, azimuth, elevation, and ksys.

Returns:

beamcodes – Radar beamcode array

Return type:

np.ndarray

generate_errors(rel_err, err_ref_rng)[source]

Generate error values associated with each radar measurment. This is a simple approximation where errors are proportional to the distance to the radar squared.

err = C*r^2

Here, C is rel_err and r is the radar slant range divided by err_ref_rng, such that the ouput will have the specified relative error at the specified reference range.

Parameters:

  • rel_err (float) – Relative error

  • err_ref_rng (float) – Error reference range, or the range at which the output error equals the specified rel_err

Returns:

  • ne_err (np.ndarray) – Electron density error at the fitted range gates

  • ti_err (np.ndarray) – Ion temperatrue error at the fitted range gates

  • te_err (np.ndarray) – Electron temperatrue error at the fitted range gates

  • vlos_err (np.ndarray) – LoS velocity error at the fitted range gates

  • ne_notr_err (np.ndarray) – Electron density error at the ACF range gates

generate_fitted_params()[source]

Generate FittedParams, FitInfo, and NeFromPower output dictionaries. These are the main outputs that contain actual measurements and information about the measurements.

Returns:

  • FittedParams (dict) – Main fitted meausrement output

  • FitInfo (dict) – Information about the quality of fit

  • NeFromPower (dict) – Measruements from the ACF range gates (electron density only)

generate_geomag()[source]

Generate dictionary with fitted range gate coordinates and information.

Returns:

Geomag – Coordinates of fitted range gates

Return type:

dict

generate_radar_measurements()[source]

Generate the basic radar measurmeents at each point in the field-of-view. These include: * Elecron density (Ne) * Ion temperature (Ti) * Electron temperature (Te) * Line-of-Site plasma velocity (Vlos)

Returns:

  • ne (np.ndarray) – Electron density at the fitted range gates

  • ti (np.ndarray) – Ion temperature at the fitted range gates

  • te (np.ndarray) – Electron temperature at the fitted range gates

  • vlos (np.ndarray) – Line-of-Site velocity at the fitted range gates

  • ne_notr (np.ndarray) – Electron density at the ACF range gates

generate_site()[source]

Generate Site dictionary containing information about the site coordinates.

Returns:

Site – Coordinates for the site in various systems

Return type:

dict

generate_time()[source]

Generate dictionary of the various time formats included in the standard output.

Returns:

Time – Various formats for output timestamps

Return type:

dict

generate_time_array(starttime, endtime)[source]

Generate time arrays.

Parameters:

  • starttime (datetime.datetime) – Start time for synthetic data

  • endtime (datetime.datetime) – End time for synthetic data

Returns:

  • utime (np.ndarray of floats) – Array of unix timestamps

  • time (np.ndarray of datetime.datetime) – Array of datetime.datetime objects

noisy_measurements()[source]

Return the radar measurements with gaussian random noise proportional to their error measurements.

Returns:

  • ne (np.ndarray) – Noisy electron density at the fitted range gates

  • ti (np.ndarray) – Noisy ion temperature at the fitted range gates

  • te (np.ndarray) – Noisy electron temperature at the fitted range gates

  • vlos (np.ndarray) – Noisy line-of-Site velocity at the fitted range gates

  • ne_notr (np.ndarray) – Noisy electron density at the ACF range gates

Radar

class amisrsynthdata.radar.Radar(config)[source]

Bases: object

Class describing the radar attributes used to create synthetic data.

Parameters:

config (yaml) – Radar configuration parameters

beams_from_az_el(beam_azimuth, beam_elevation)[source]

Generate beamcodes and ksys constants for beams defined by an arbitrary azimuth and elevation. Beamcodes are assigned sequentially starting at 90001 to differentiate them easily from “standard” beamcodes.

Parameters:

  • beam_azimuth (np.ndarray) – Azimuth of each beam [deg]

  • beam_elevation (np.ndarray) – Elevation of each beam [deg]

Returns:

  • beamcodes (np.ndarray) – Beamcode number for each beam

  • beam_ksys (np.ndarray) – Ksys of each beam

Note

The ksys values are usually determined experimentally and are not significant for any of the geometry-based calculations performed by this code. The array returned is the correct size, but filled with NaNs as placeholders.

beams_from_beam_codes(beamcodes)[source]

Find the azimuth, elevation and ksys constant for beams given their standard beamcode.

Parameters:

beamcodes (np.ndarray) – List of AMISR beamcodes

Returns:

  • beam_azimuth (np.ndarray) – Azimuth of each beam [deg]

  • beam_elevation (np.ndarray) – Elevation of each beam [deg]

  • beam_ksys (np.ndarray) – Ksys of each beam

Note

The ksys values are usually determined experimentally and are not significant for any of the geometry-based calculations performed by this code. The array returned is the correct size, but filled with NaNs as placeholders.

calculate_acf_gates(slant_range_config)[source]

Calculate the position of the range gates used by the autocorrelation functions pre-summing. These positions are used for the non-fitted density calculations (NeFromPower) and are at a higher resolution than the typical fitted parameters.

Parameters:

slant_range_config (list of floats) – [start, stop, step] of the ACF slant ranges [m]

Returns:

  • slant_range (np.ndarray) – Slant range positions [m]

  • lat (np.ndarray) – Geodetic latitude of each range gate in each beam [deg]

  • lon (np.ndarray) – Geodetic longitude of each range gate in each beam [deg]

  • alt (np.ndarray) – Geodetic altitude of each range gate in each beam [m]

calculate_gates(alt_bins_config)[source]

Calculate the positions of the fitted parameter range gates

Parameters:

alt_bins_config (list of floats) – [start, stop, step] of the altitude bins to be used for fitted parameter range gates

Returns:

  • slant_range (np.ndarray) – Slant range positions [m]

  • lat (np.ndarray) – Geodetic latitude of each range gate in each beam [deg]

  • lon (np.ndarray) – Geodetic longitude of each range gate in each beam [deg]

  • alt (np.ndarray) – Geodetic altitude of each range gate in each beam [m]

kvec_all_gates()[source]

Calculate the components of the look vector for every range gate.

Returns:

kvec – Local geodetic components [E, N, U] of the radar look direction at each range gate

Return type:

np.ndarray

Ionosphere

class amisrsynthdata.ionosphere.Ionosphere(config)[source]

Bases: object

Class describing the ionosphere used to create synthetic data.

Parameters:

config (yaml) – Ionosphere configuration parameters

density(utime, glat, glon, galt)[source]

Calculate density at the requested times and locations

Parameters:

  • utime (float or np.ndarray) – Unix Time

  • glat (float or np.ndarray) – Geodetic Latitude

  • glon (float or np.ndarray) – Geodetic Longitude

  • galt (float or np.ndarray) – Geodetic Altitude

Returns:

Density values at each of the input times and locations

Return type:

float or np.ndarray

etemp(utime, glat, glon, galt)[source]

Calculate electron temperature at the requested times and locations

Parameters:

  • utime (float or np.ndarray) – Unix Time

  • glat (float or np.ndarray) – Geodetic Latitude

  • glon (float or np.ndarray) – Geodetic Longitude

  • galt (float or np.ndarray) – Geodetic Altitude

Returns:

Electron temperature values at each of the input times and locations

Return type:

float or np.ndarray

itemp(utime, glat, glon, galt)[source]

Calculate ion temperature at the requested times and locations

Parameters:

  • utime (float or np.ndarray) – Unix Time

  • glat (float or np.ndarray) – Geodetic Latitude

  • glon (float or np.ndarray) – Geodetic Longitude

  • galt (float or np.ndarray) – Geodetic Altitude

Returns:

Ion temperature values at each of the input times and locations

Return type:

float or np.ndarray

velocity(utime, glat, glon, galt)[source]

Calculate velocity at the requested times and locations

Parameters:

  • utime (float or np.ndarray) – Unix Time

  • glat (float or np.ndarray) – Geodetic Latitude

  • glon (float or np.ndarray) – Geodetic Longitude

  • galt (float or np.ndarray) – Geodetic Altitude

Returns:

Velocity components at each of the input times and locations

Return type:

np.ndarray

Note

The returned velocity array will be one dimension larger than the input time and coordinate arrays to account for the three velocity components (east, north, up)

zero_array(ut, x, vec=False)[source]

Generate an array of zeros of the correct output shape based on input time an coordinate arrays. This can then be indexed and populated with values.

Parameters:

  • ut (float or np.ndarray) – time or time array

  • x (float or np.ndarray) – coordinate or coordinate array

  • vec (bool) – Flag indicating whether or not the returned array should add a dimension for vector components

Returns:

Either float 0.0 for scalar input or an array full of zeros of the correct shape

Return type:

float or np.ndarray